H-305-E adapter sleeve: complete specifications & mounting data
The H-305-E is an adapter sleeve sized 25 x 38 x 29 mm (tapered bore x sleeve OD x width) for a plain 20 mm metric shaft with M 25x1,5 thread supplied with the KMFE 5 lock nut at 76 g per ISO 2982-1. Verify dimensions against the official catalog before ordering.
Specification table
| Parameter | Value |
|---|---|
| Brand | SKF |
| Bore diameter d | 25 mm |
| Outer diameter D | 38 mm |
| Width B | 29 mm |
| Fits shaft diameter | 20 mm |
| Sleeve thread G | M 25x1,5 |
| Included lock nut | KMFE 5 |
| Material | Carbon_Steel |
| Mass | 76 g |
| Manufacturer designation | H 305 E |
| Standard | ISO 2982-1 |
| Catalog version | SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 23.1 adapter sleeves for metric shafts |
| Last verified | 2026-09-30 |
Source: catalog reference (SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 23.1 adapter sleeves for metric shafts) · extracted 2026-09-30
Parameters extracted from the official SKF Rolling Bearings catalogue (SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 23.1 adapter sleeves for metric shafts); SKF® and SKF Explorer® are trademarks of AB SKF, used here for identification only — mpnbase is not an authorized SKF distributor. Boundary dimensions are ISO 15 interchangeable; current production values may differ, verify at skf.com.
Dimensions in inches & H3-series range
| Bore d | 0.984 in |
|---|---|
| Outer diameter D | 1.496 in |
| Width B | 1.142 in |
| ISO bore code | — |
| Radial section height (D−d)/2 | 6.5 mm |
| Smallest bore in H3-series | 20 mm |
| Largest outer diameter in H3-series | 145 mm |
| Width range across H3-series | 28–77 mm |
| Bore position in H3-series (smallest first) | 2 of 18 |
| Bore above smallest H3-series size | 5 mm |
Cross references & equivalents
| Equivalent model | Brand | Match level | Note |
|---|---|---|---|
| H | ISO 15 | full Dimensions and internal design equivalent — standard interchange. | ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier. |
Interchange levels: full standard interchange · partial verify parameters · verify manual confirmation required. Links resolve to the equivalent model's specification page where available.
How the H-305-E model number is decoded
mounting and dismounting stay purely mechanical: the KMFE 5 nut drives the taper home, and backing the nut off releases the 25 mm seat without oil-injection tooling the seat taper is 1:12, so each millimetre of axial drive-up removes about 1/12 mm of radial clearance; one turn of the KMFE 5 nut on the M 25x1,5 thread advances 1.5 mm and takes out roughly 0.125 mm of clearance the OD-to-bore ratio is 1.52: the 38 mm sleeve OD is only 6.5 mm of section beyond the 25 mm seat, leaving room for the bearing outer ring without enlarging the housing bore the KMFE 5 lock nut carries size index 5, matching the bore-code family of the 25 mm seat; the nut engages the M 25x1,5 sleeve thread over its full width at 76 g drive-up is still a hook-spanner job on the KMFE 5 nut slots, with feeler gauges checking clearance reduction rather than torque controlling the fit the 20 mm shaft size sits at the bottom of the range, where the thin sleeve wall and fine M 25x1,5 thread call for measured drive-up rather than forceful tightening reading H 305 E: the trailing E means the sleeve ships with a KMFE 5 lock nut whose built-in locking element replaces the MB washer, cutting one part from the bill of materials the H3 designation block places it in the medium-section H 3 range, the default seat for 13..K and 22..K self-aligning ball bearings and 222..K spherical roller bearings — every sleeve in the block uses the same bore-code logic, and here the 25 mm tapered bore matches the K-suffix bearing it is ordered for hardware on this row: the KMFE 5 lock nut; a hook spanner turns the nut while feeler gauges monitor the 25 mm bore typical applications include industrial fan and blower impeller shafts, gearbox input and output shafts and pump shafts in water and process plants adapter sleeves earn their place wherever a tapered-bore bearing must sit at any axial position on a plain shaft — here a 25 mm bore bearing on a 20 mm shaft in pump shafts in water and process plants the sleeve lets the designer use a plain, unstepped shaft and still locate the bearing positively; only one shoulder is needed, opposite the KMFE 5 nut ordering digest — H 305 E: 20 mm plain shaft to 25 mm tapered bore, sleeve 38 mm OD and 29 mm wide, thread M 25x1,5, supplied with KMFE 5 self-locking nut; listed mass is 76 g
Typical equipment & failure modes
Common applications
- marine winch and deck machinery shafts
- industrial fan and blower impeller shafts
- cement plant kiln and mill trunnion drives
- food processing line drive shafts
Known failure patterns
- interchanging nut families (KM vs KMFE, MB vs MS) across executions loses locking reliability even when the thread appears to fit
- a fretted or corroded shaft seat cannot be rescued by a new sleeve — the thin wall conforms to the damage and clamping force collapses
- the integral locking screw must be set to the catalogue torque; over-setting galls the M 25x1,5 thread and makes removal difficult
- neglecting the catalogue axial displacement value leaves the bearing either loose on the taper or preloaded hot in service
- driving the bearing via the outer ring during mounting loads the rolling elements; force is always applied through the lock nut on the inner ring
Selection pitfalls — read before you substitute
- interchanging nut families (KM vs KMFE, MB vs MS) across executions loses locking reliability even when the thread appears to fit
- the integral locking screw must be set to the catalogue torque; over-setting galls the M 25x1,5 thread and makes removal difficult
- over-driving the taper eliminates bearing internal clearance entirely; clearance reduction must be measured with feeler gauges, not estimated from nut torque
Frequently asked questions
What shaft size does the H-305-E adapter sleeve fit?
H 305 E is listed for a 20 mm plain shaft; its tapered bore accepts 25 mm K-suffix bearings, the sleeve measures 38 mm OD and 29 mm wide.
What does the H 305 E designation mean?
H 305 E: H-series metric adapter sleeve in the H3 dimension plan; the code resolves to a 25 mm tapered bore and a 20 mm shaft.
What is supplied with the H-305-E?
Supplied hardware is the KMFE 5 lock nut. No hydraulic tooling is listed for the 20 mm shaft size.
How much does the H-305-E adapter sleeve weigh?
It weighs 76 g; the figure is the sleeve-only catalogue mass, with the KMFE 5 nut counted on the same product row but the hydraulic tool ordered separately.
How is the H-305-E mounted on the shaft?
Slide the sleeve onto the 20 mm plain shaft against the abutment, fit the bearing, turn the KMFE 5 nut with a hook spanner until the measured clearance drop matches the table, and lock it via its integral screw.
Reviewed & verified by the MPN Base engineering desk against source catalog SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 23.1 adapter sleeves for metric shafts on 2026-09-30. Read our editorial & correction policy.